In a large cohort, obese individuals Yanoff demonstrated significantly lower serum iron (75.8 ± 35.2 vs. 86.5 ± 34.2 g/dL), higher ferritin (81.1 ± 88.8 vs. 57.6 ± 88.7 mg/L), elevated transferrin receptor (22.6 ± 7.1 vs. 21.0 ± 7.2 nmol/L), and markedly higher CRP (0.75 ± 0.67 vs. 0.34 ± 0.67 mg/dL), with obesity conferring a higher prevalence of iron deficiency by serum iron and transferrin receptor criteria. The gene discussed is CRP; the disease is obesity due to melanocortin 4 receptor deficiency.